Mechanical counters

ABSTRACT

The invention relates to electromagnetically controlled counters in which a checking circuit is provided for checking the operation of the counter and for preventing further counting if the operation is found to be faulty. It includes both transistorized methods and relay methods of operation and may be applied to single counters or banks thereof.

United States Patent Inventors Manfred Huber;

Norbert Klimek, both of London, England Appl. No. 726,171 Filed May 2, 1968 Patented July 6, 1971 Assignee English Numbering Machines Limited Enfleld, England Priority May 9, 1967 Great Britain 21 ,395/65 MECHANICAL COUNTERS 4 Claims, 6 Drawing Figs.

US. Cl 235/92, 328/49. 235/153 Int. Cl 606m 3/12 Field of Search 235 /92,

[56] References Cited UNITED STATES PATENTS 3,442,422 1/1969 Frank. r 340/347 3,051,855 8/1962 Lee Y .W 307/885 2,597,428 5/1952 Bachelet 177/311 2,973,145 2/1961 Daniels 235/132 Primary Examiner-Daryl W. Cook Assistant Examiner-Robert F. Gnuse Attorney-Nolte and Nolte ABSTRACT: The invention relates to electromagnetically controlled counters in which a checking circuit is provided for checking the operation of the counter and for preventing further counting if the operation is found to be faulty. It includes both transistorized methods and relay methods of operation and may be applied to single counters or banks thereof.

PATENTEflJuL 61971 591,77 4

sum 1 OF 5 INVENTORS MANFRED HUBER NORBERT KLIMEK INVENTORS MANFRED HUBER NORBERT KLIMEK ATTO EYS PATENIED JUL 6 I97] sum 2 0F 5 PATENTEI] JUL 6 I971 SHEET 3 BF 5 INVENTORS MANFRED HUBER NORBERT KLIMEK mm ATTO NEYS PATENTED JUL SL971 SHEET l [1F 5 INVENTORS MANFRED HUBER NORBERT KLIMEK NEYS This invention relates to mechanical counters and more specifically to mechanical counters whose operation is controlled by an electromagnet.

It is an object of the invention to provide for such counters means for checking that the counter is operated by such counting signal received.

It is a further object of the invention to provide means for preventing the receipt of further counting signals if the counter is not operated by a counting signal received.

SUMMARY OF THE INVENTION According to the invention, a mechanical counter comprises an electromagnet, an armature controlled by the electromagnet, a number wheel rotatable in steps and actuatable by the armature for indicating a count, a check signal means for providing a check signal on completion of each step.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 2, A, B, and C, assembled as shown in FIG. 1 show'a counter arrangement comprising three banks of counters 1, 2 and 3. Each bank has ten single digit counters a to j. Each counter has an electromagnet 4, an armature 5, and a number wheel driven by the armature in any suitable manner for example by a pawl and ratchet mechanism. Such an arrangement is shown diagrammatically for the counter 3j. Each electromagnet for the counters is connected by one of a plurality of rectifiers 10 to on'e of a plurality of selector transistors 11 which when conducting connect the electromagnet to earth as indicated by the -volts line 12. Operation of the selector transistors 11 is controlled by one of three program units l4, l and 16 by way of NoR gates 18 coupled to the base of the respective transistor 11.

The electromagnets 4 of the counters are connected together in each of the groups 1, 2 or 3 as at 13 and are further.

connected to switching means 20 controllable by a bank selection NAND-gate 21 through an inverter 22. When the switching means 20 are conducting, one side of the electromagnets are connected to a voltage supply VI of, for example, +40. The switching means 20 are operated by the NAND- gate 21, the two inputs of which are the output of a monostable device 23 and a select-bank input 24. The monostable device 23 is connected to one output of a bistable device 25 and through a NAND-gate 26 to a counting pulse input 27 when operation of the NAND-gate is selected by a select counting input 28. The bistable device is also connected to a voltage supply V2 of, for example, +5.

Each of the number wheels 6 of the counting units is mechanically connected to a rotary wiper 30 which is rotatable with its respective number wheel. This wiper slides across a printed circuit pad, which includes a bus pad 31 and contact elements 32. The arrangement is such that the wiper moves between one nonconducting area between two contact elements 32 to an adjacent nonconducting area each time a count of one digit is recorded by the counter unit. It will be appreciated that one wiper set is provided for each counter unit in each bank, only one being shown for each bank for purposes of simplicity.

Connected between the output of the monostable and the bistable device 28 is a warning circuit consisting of a loudspeaker or horn 36 and indicator lamp 57. The lamp or loudspeaker are controlled by a switch circuit 38 whichis in turn controlled by a NAND-gate 39 through an inverter 40, one

gate input being taken from the bistable device 25 and the other gate input being taken through an inverter 42 from the monostable device 23. A time delay for the operation of the warning circuit is provided by capacitor 44 to prevent warning being given during normal working.

The operation of the counter will now be described, the pul ses of which operation are shown in FIG. 3:

Assuming that it is desired to set up the figures 0000000245 in the third group of counters it is first necessary to provide 5 counting pulses to the counter 3]. To this end one of the programming units is used and it will be assumed that for this purpose the program unit 16 is used.

First the program unit is set to select the counter j which will feed a signal (FIG. 3 at a) to the NOR-gate l8 to'the base of the selector transistor 11]. This will select all of the counters lj, 2j, 3 by connecting the electromagnets 6 to earth (i.e. 0 volts). The bank required is selected by means of the bank selection signal (indicated at b in FIG. 3) which in this case will select the bank 3 and will provide an initial input to the respective NAND-gate 21 enabling the NAND-gatc to pass counting pulses from the monostable device 23. A select counting signal is fed to the NAND-gate 26 which will admit counting pulses for example, of microseconds in length, which are fed to the other input of the NAND-gate. The pulses may be repeated, for example, at intervals of 20 milliseconds. These counting pulses from the input 27 are passed to the bistable device 25 which will be set to the condition a providing a pulse output to the monostable 23 as indicated at d in FIG. 3. The monostable output indicated at e in FIG. 3 provides a pulse to the NAND-gate 21 through the invertor 22 and operates the switching circuit 20 to supply, during the duration of the pulses, +40 from the Voltage supply V1 to the electromagnet 4 of the counter 3 which, on release at the trailing edge ofthe pulse, moves on by one digit.

The setting of the bistable device to the a condition prevents further counting pulses from passing therethrough until it is reset to the b condition. Movement of the number wheel 6 in response to the counting impulse passing through the electromagnet 4 will also move the associated wiper 30 from its position between the contacts 32, across one contact 32 and into the space between it and the next contact. This will provide for a reset signal by connecting the voltage V2 to earth by way of resistance 34 and the point indicated at 35 will be at zero potential. This will reset the bistable device 25 to the b condition permitting the bistable to receive a further counting pulse. g in FIG. 3 is a pulse formation controlling operation of the electromagnet and It shows the form of the reset pulse which resets the bistable device 25. Thus the pulses will continue to operate the counter until 5 has been set up thereon, whereupon the program unit will deenergize the transistor llj and energizes the transistor Ill for four pulses. Thereafter the transistor 11h is energized for two pulses, thus setting up the required number in the counter bank.

If at any time the counter which is being pulsed does not operate, the wiper 32 will not move correctly from its position between two contacts 32 to its next position between contacts 32 and therefor the bistable device will not be reset. This operates the warning device by providing an output from the monostable device 23 and bistable device 25 through the NAND-gate 39 and inverter 40 to the switch circuit 38 to operate the warning lamp 37 and horn 36. As can be seen, with failure of any one counter unit to operate, further counting will not be carried out and warning will be given.

It will be understood that any number of banks of counter units can be used, each counter unit having its own contact wiper. The program units are usually used to carry out various programs the results of which will be indicated on the various counter groups as necessary. It will also be understood that where the NAND-gates and NOR-gates have been used it is equally possible touse AND- and OR-gate with suitable invertion of the signals. Thus where an AND-gate is used instead of the NAND-gate 21 the inverter 22 will be omitted, similar alterations being made for the NAND-gates 26 and 39 and for the NOR-gates 18.

A second embodiment of the invention is shown in FIG. 4, which shows a system of relays instead of the electronic con,- trol which is used inthe first embodiment. in this embodiment, only the relay control of one counter unit is shown, the other circuitry for the other counter units and also for the pulse generation and transfer being omitted. The counter unit is indicated at 100 and is coupled to a pulse input 101 by means of switch contact 102. The counter is also connected to an earthline 103 across which is positioned a relay coil 105 provided with a time delay circuit 106. Means inside the counter 100 provide for a checking signal which passes to a relay coil 107. Both of the relay coils 105 and 107 control the operation of the switch 103 which is thus operated on the double acting principle.

ln operation the pulses fed down the line 101 pass through the switch to the counter to cause a count of one digit to be registered. This pulse also operates a relay coil 105 to open the switch after the delay has taken place allowing for the pulse to reach the counter. If the counter counts correctly a check signal is provided by the counter and energizes the relay coil 107 to close the switch 103 ready for the next pulse. Should the counter fail to count correctly the check signal would not be provided and the switch 103 would remain open, thus preventing any further pulses from passing to the counter.

[t is clear that the checking circuit as describedin the first embodiment may be used to check any number of banks of single digit counters with certain limitations. For example, if there is a number of program units which control the selector transistors, only one program unit may be used in any counting cycle. Similarlyonly one bank may be selected in any counting cycle and the number of single digit counters per bank is directly related to the number of controlling positions of each program unit and there must not be more counter units than thosecontrolling positions. Where a number of banks of single digit counters are required to be used simuldigit counter.

In most cases the banks wouldv not be used in this way and any necessary transfers would be provided in the program unit the banks being used for indication purposes only.

It will be appreciated that the above described embodiments are given by way of example only and that various modifications may be made to the above described embodiments'without departing from the scope and spirit of the invention. 1

lclaim: 1 l. A mechanical counter comprising a gate element for receiving a counting signal, a bistable element fed with counting signals by said gate element and being settable into a first condition by a counting signal in which condition it is unafr fected by a succeeding counting signal, a monostable element actuatable through said bistable element when in said first condition, an electromagnet whose energization is controlled by said monostable element, an armature controlled by said electromagnet, a number wheel rotatable in steps and actuatable by said armature for indicating a count, a contact element movable in steps with said number wheel, an electric circuit for initiation of a check signal checking each counting step taneously it is, of course, necessary to provide duplication of circuits in order that this may be done.

The counter of the invention could also be used as a multidigit counter the number wheels for each digit counter unit and controlled by movement of said contact element, said circuit providing a signal to said bistable element for setting said bistable element from said first condition to a second condition in which said bistableelement receives further counting signals.

2. An electromechanical counter comprising a source of counting pulses, an electromagnet, a bistable switching means coupling said counting pulse source to said electromagnet, an armature actuated by the electromagnet in response to each pulse passed through said bistable switching means, circuit means to apply each pulse passed by said bistable switching means to render said bistable switching means nonconductive, a number wheel rotatable in steps by means of said armature, a contact element movable in steps with said number wheel, an electric circuit responsive to each stepping movement of said contact element to generate a transient check signal, circuit means to apply said check signal to an input of said bistable switching means to return said bistable switching element to its conductive state.

3. An electromechanical counter as defined in claim 2, comprising an electronic bistable circuitelement providing the bistable switching means.

4. An electromechanical counter as defined in claim 2, wherein the bistable switching means comprises switch means actuable by a double-acting relay. 

1. A mechanical counter comprising a gate element for receiving a counting signal, a bistable element fed with counting signals by said gate element and being settable into a first condition by a counting signal in which condition it is unaffected by a succeeding counting signal, a monostable element actuatable through said bistable element when in said first condition, an electromagnet whose energization is controlled by said monostable element, an armature controlled by said electromagnet, a number wheel rotatable in steps and actuatable by said armature for indicating a count, a contact element movable in steps with said number wheel, an electric circuit for initiation of a check signal checking each counting step and controlled by movement of said contact element, said circuit providing a signal to said bistable element for setting said bistable element from said first condition to a second condition in which said bistable element receives further counting signals.
 2. An electromechanical counter comprising a source of counting pulses, an electromagnet, a bistable switching means coupling said counting pulse source to said electromagnet, an armature actuated by the electromagnet in response to each pulse passed through said bistable switching means, circuit means to apply each pulse passed by said bistable switching means to render said bistable switching means nonconductive, a number wheel rotatable in steps by means of said armature, a contact element movable in steps with said number wheel, an electric circuit responsive to each stepping movement of said contact element to generate a transient check signal, circuit means to apply said check signal to an input of said bistable switching means to return said bistable switching element to its conductive state.
 3. An electromechanical counter as defined in claim 2, comprising an electronic bistable circuit element providing the bistable switching means.
 4. An electromechanical counter as defined in claim 2, wherein the bistable switching means comprises switch means actuable by a double-acting relay. 